From 45fe93dff2fb58b22de04c729f8447ba0f773d93 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Mon, 24 Jul 2017 11:28:04 +0100 Subject: crypto: algapi - make crypto_xor() take separate dst and src arguments There are quite a number of occurrences in the kernel of the pattern if (dst != src) memcpy(dst, src, walk.total % AES_BLOCK_SIZE); crypto_xor(dst, final, walk.total % AES_BLOCK_SIZE); or crypto_xor(keystream, src, nbytes); memcpy(dst, keystream, nbytes); where crypto_xor() is preceded or followed by a memcpy() invocation that is only there because crypto_xor() uses its output parameter as one of the inputs. To avoid having to add new instances of this pattern in the arm64 code, which will be refactored to implement non-SIMD fallbacks, add an alternative implementation called crypto_xor_cpy(), taking separate input and output arguments. This removes the need for the separate memcpy(). Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu --- crypto/ctr.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'crypto/ctr.c') diff --git a/crypto/ctr.c b/crypto/ctr.c index 477d9226ccaa..854d924f9d8e 100644 --- a/crypto/ctr.c +++ b/crypto/ctr.c @@ -65,8 +65,7 @@ static void crypto_ctr_crypt_final(struct blkcipher_walk *walk, unsigned int nbytes = walk->nbytes; crypto_cipher_encrypt_one(tfm, keystream, ctrblk); - crypto_xor(keystream, src, nbytes); - memcpy(dst, keystream, nbytes); + crypto_xor_cpy(dst, keystream, src, nbytes); crypto_inc(ctrblk, bsize); } -- cgit v1.2.3